A state-of-the art aircraft comprises a certain number of flight control surfaces which allow certain axes of the aircraft to be controlled. In particular, an aircraft comprises at least one crocodile-type flight control surface, in other words a flight control surface comprising two foil flaps, each one being rotationally movable. The two foil flaps are disposed one against the other and each one is rotationally controlled by an actuator. The two foil flaps can therefore be controlled independently one of the other, either in the same rotational direction or in opposing rotational directions to move one away from the other, thereby exhibiting a shape identical to that of an open crocodile mouth.
When the two foil flaps are displaced in the same direction, they behave like a one-piece aileron or a flight direction control surface and when the two foil flaps are displaced in opposing directions, they behave like an air brake.
At present, the rigidity of a crocodile-type flight control surface of this kind is guaranteed by the internal rigidity of each foil flap, which requires heavy foil flaps to be put in place.